Modern vehicles may be equipped with a multitude of devices that intervene in the vehicle operation in a regulating or controlling manner. Among these are, in particular, electronic stability systems (such as ESP), automatic braking systems (such as ABS), driver assistance systems (such as ACC), restraining systems (such as airbag systems), as well as a variety of value-added functions, for instance an automatic cornering light or starting-traction control (such as HHC).
Each system utilizes sensors whose signals are read and processed and on whose basis a control or regulation operation is implemented. In order to avoid false triggering of the systems, the sensor signals are usually filtered and subjected to a plausibility check. This ensures that the system takes only plausible signals into account. If implausible signal values occur, the known systems usually respond by restricting functions (default level) or, in the extreme case, by complete deactivation of the system. The signal monitoring normally takes place in the control device of the particular vehicle system.
In general, at least single-signal monitoring, during which the value range and/or the gradient of the signals is checked and possibly occurring sensor reports are analyzed, is implemented within the framework of plausibilization. It is also known to compare the sensor signals to estimated values that were calculated from various other sensor signals (so-called model-based plausibilization).
The known plausibilization methods may function sufficiently well during normal vehicle operation. However, in extreme driving situations, such as after a collision, signal values or signal changes may occur that far exceed the plausible range. The sensor signals in question are then considered implausible or they are falsified by excessive filtering. This may lead to the particular system switching into a default mode with reduced functional scope or to the system automatically deactivating itself. If safety-relevant systems such as an electronic stability program are involved, the driving safety may be reduced as a result. This is especially critical in offset rear collisions or offset side collisions during which a high yaw moment is acting on the vehicle, which induces rapid rotation of the vehicle. Without additional assistance devices, the vehicle may possibly get out of control completely and cause secondary accidents that may have serious results if high speeds are involved.